Periodicals of Engineering and Natural Sciences (PEN - International University of Sarajevo)
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Experimental and theoretical calculation of efficiency for flat plate solar collectors in Erbil city
Get PDFSolar plate collectors are utilized to heat up water or a mixture of water and glycol by capturing solar radiation and transfer this heat to the collector fluid. In this study, the efficiency of solar plate collector during 19th, 20th and 21st of February, was investigated experimentally. The time of day, plate collector mean temperature, solar intensity and external air temperature can effect on the efficiency of solar collector. And the effect of incidence angle on solar irradiation has been studied; as a result, the solar irradiance will be decreased as the angle of incidence increased. A method presented can be used to calculate hour angle, diffuse solar radiation and total solar radiation at various temperatures in this paper its MATLAB programs
Reactive protocols for unified user profiling for anomaly detection in mobile Ad Hoc networks
Get PDFThe Next Generation mobile network expected to be fully automated to meet the growing need for data rates and quality in communication. These prodigious demands have also increased the amount of data being handled in these wireless networks. The cellular networks can leverage vital data about the user and the network conditions providing all-inclusive visibility and intelligence in communication. Emerging analytic technologies such as big data and neural networks have been used to unearth vital insight from network traffic to assist intelligent models in routing packets. Reactive protocols are an emerging model in the intelligent routing of traffic in ad-hoc networks. In this paper, we first utilize the reactive protocols to route traffic in a wireless network while analyzing anomalous behavior. In the case of anomaly detection in wireless communication, combined performance indicators to identify outliers. The detected outliers been compared with the ground data and routes created using the reactive protocols. The combination of reactive protocols and the key performance indicators in network performance uncovered anomalies leading to segregation of these traffic in routing. From the results, it is evident that an abrupt surge in the traffic indicated an anomaly and identify the areas of interest in a network especially for resource and path allocation and fault avoidance. A MATLAB GUI was used to simulate the reactive protocols for routing of traffic and generation of datasets that analyze in Microsoft Excel to characterize the key performance indicators of the network
Time and frequency analysis of vostok ice core climate data
Get PDFThe periodicity of Vostok ice core climate temperature and gas concentration data indicate inherent long term past regularity of Earth’s climate, with a period of around 100,000 years, warming around 15,000 and cooling of around 85,000 years. At this point we are at the top of one of the warming periods. Vostok data cover around 430,000 years, ie 4 climate cycles (warming-cooling), of similar but not quite the same duration. In this paper we perform a detailed time and frequency analysis of these data for each of the cycles as well as their various combinations, including a full tested period of 430,000 years. Time correlation analysis allows for more accurate time lag estimate in each cycle already noted between temperature change and carbon dioxide content. We estimate these lags to lie between 1000-2500 years, longer than previously concluded. On the frequency side we perform Fast Fourier Analysis and identify full spectrum of harmonics for various cycles, and then perform energy analysis to identify which of the harmonics contributes the most. The idea is to reduce the computational load for further modeling and analysis using Kalman Filter based prediction method. Once the prediction model is defined (a follow up paper) data will be split into two segments, Learning and Testing, in preparation of a Machine Learning fine tunning methodology. We can use last three or last two or even just last cycle to learn on, and then the current on going cycle to test on. This will result in real time prediction of relevant climate data. Assuming causal time regularity, more of these cycles are employed in training, more the prediction error for the next cycle should be reduced. Hence it is critical to perform very detailed time and frequency analysis of Vostok data as a solid data base for the prediction model to follow. 
Optimization of water-cement ratio in concrete contains recycled polypropylene (PP) plastic waste
Get PDFRecently, the use of recycled plastic waste in civil engineering applications has been increased. This paper aims to investigate the effect of water-cement ratio on the compressive strength of concrete that contents 2.5 % polypropylene (PP) as plastic waste. Two references concrete mixes were prepared. The first mix had a water-cement ratio of 0.45 with 2.5% plastic waste, the second mix with 0.45 water cement ratio but without plastic waste. Three concrete mixes with water cement ratios of (0.5, 0.4, and 0.3) were also used as parametric study cases. The results indicated that decreasing the water-cement ratio from 0.45 to 0.4 increases the compressive strength by 20.2%. In addition, the compressive strength increases by 36.2% with decreasing of water cement ratio from 0.45 to 0.3. While the compressive strength decreases by 12% with the increase of water-cement ratio from 0.45 to 0.5
The influence of information technology (IT) on organization leadership and performance
Get PDFLeadership of modern organizations depend upon ever greater levels of information technology (IT) now, such as big data and management & data analytics, a trend which shows no sign of abating now. However, not all modern organizations have benefited from such IT investments, resulting in mixed perceptions on the value of IT. Organizations must be knowledgeable in order to properly utilize IT tools and be able to apply that knowledge to create unique competencies in order to gain sustained advantage from IT investments. Information technology in the modern organizations has been proposed as the mechanism to accomplish the leadership in the concerned industries. Existing empirical research demonstrates that IT may indeed act as a mediator for the effect of leadership on modern organizational outcomes. Yet, this study is not consistent in the conceptualizations of the relationships involved, nor in their definitions and measurement of IT investment spending. Thus, they chase numerous creative and innovative procedures and approaches while adding a substantial role of informational technology in the administration of such practice. This study aims to address these concerns in an organization setting by using structural equation modelling (SEM) to compare the effectiveness of descriptive and normative measures of IT as mediating variables in knowledge-intensive organizations. Implications for research and practice are discussed
Nonlinear Estimation of Quadcopter States Using Unscented Kalman Filter
Get PDFIn recent years, using Unmanned Arial Vehicles (UAV) like quadcopter in civilian and military fields are increased dramatically. Performance and robustness are the most important specifications required for most applications. Different sensors are usually used for a quadcopter to provide the necessary measured states (attitude and position) for control. The white noise generated by physical sensors is one of the important issues that affect the quality of states measurements. The available solutions are still have limited performance for a wide range of nonlinearity. In this paper, Unscented Kalman Filter (UKF) is proposed as a robust estimator that has the ability to work efficiently with high nonlinear systems. Modified PID (PI-D) controller which has better properties than traditional PID controller is used with proposed filter in order to get better performance of quadcopter. The obtained results are compared with that of Extended Kalman Filter (EKF) and proved to be more reliable. Moreover, the results show that the proposed filter largely decreases the error generated by noise and improves the performance of quadcopter better than the EKF
The road to the blockchain technology: Concept and types
Get PDFAs the Bitcoin keeps increasing in value compared to other cryptocurrencies, more attention has given to Blockchain Technology (BT), which is the infrastructure behind the Bitcoin, especially on its role in addressing the problems of the classical centralized system. As a digital currency, Bitcoin is dependent on the decentralized cryptographic tools and peer-to-peer system. The digital currency implements a distributed ledger using Blockchain when verifying any type of transaction. In this paper, the aim is to describe how digital currency networks such as Bitcoin provides a “trust-less” platform for users to embark on money transfers without necessarily depending on any central trusted establishments such as payment services or financial institutions. Furthermore, this work comprehensively overviewed the basic principle that underly BT, such as transaction, consensus algorithms, and hashing. This study also provided a novel classification for blockchain types according to their system architecture and consensus strategy. For each type, our contribution was provided with an example, which clearly describes the blockchain features and the transaction steps. Our classification intended to help researchers understand and choose the blockchain for their application. The paper ends with the discussion of the differences between each type
Operational gas turbine swirl combustors design map for pure methane and different outlet configurations
Get PDFThe most crucial phenomenon limiting gas turbine burner operation is the flashback and blowoff of flame in the combustor during gas turbine operation. In order to avoid this undesirable phenomenon, it is necessary to predict the operational map area of the gas turbine burner.
Pure methane has been taken as fuel in this analysis, which attempts to construct a design map with two swirl numbers, 1.2 and 1.5. Different configurations for the outlet of the burner ranged from open flame with a normal nozzle, to cylindrical and conical confinements.
The operation map area represents the allowance area of the burner when choosing the equivalence ratio and specified total mass flow rate. The results show that the workable area of the burner increases with the cylindrical and conical confinements, but shows no real difference between the two swirl numbers
Sustainable utilization of polyethylene terephthalate in producing local precast flooring concrete slabs
Get PDFA polyethylene terephthalate plastic material is widely used in Iraq for packages manufacturing, especially for the mineral water bottles. They turn out to be waste very rapidly due to their particular short period of use. Furthermore, the recycling amount of polyethylene terephthalate bottles is considerably fewer than the sales of virgin polyethylene terephthalate manufacture for public consumptions. In the current research, the results of rupture load, water absorption and density tests implemented on precast flooring concrete slabs reinforced by fibers prepared from waste polyethylene terephthalate bottles are reported. The fibers were prepared by the simple cutting way to the bottles of carbonated beverage, and then the fibers are incorporated in the ordinary concrete mix in different volume fraction and aspect ratio. The outcomes of the rupture load and water absorption of the plastics fibers reinforced precast flooring concrete slabs exhibited apparent increase when compared with the plain precast flooring concrete slabs. This can offer the potential and practical use of the waste plastic in the development of the production of precast flooring concrete slabs
Aspect oriented programming: Concepts, characteristics and implementation
Get PDFProgramming techniques have been passed through many development stages in their progressing path to cope with the increasing complexity of systems requirements. So, one of the main goals of the programming languages designers is how to develop programming language that can handle and manage the spread and overlapping of different functionality concerns. Because unmanageable and uncontrollable scattering of concerns inside the system may cause many problems during system running in present or/and during applying maintenance and developing the system in future. One of the most recent and powerful solutions to overcome these problems is via using Aspect-Oriented Programming (AOP) approach. This research is demonstrates the features and the problems with implying AOP techniques in the software development process